Problem: $J$ $K$ $L$ If: $ JK = 7x + 9$, $ JL = 114$, and $ KL = 9x + 9$, Find $KL$.
Answer: From the diagram, we can see that the total length of ${JL}$ is the sum of ${JK}$ and ${KL}$ $ {JK} + {KL} = {JL}$ Substitute in the expressions that were given for each length: $ {7x + 9} + {9x + 9} = {114}$ Combine like terms: $ 16x + 18 = {114}$ Subtract $18$ from both sides: $ 16x = 96$ Divide both sides by $16$ to find $x$ $ x = 6$ Substitute $6$ for $x$ in the expression that was given for $KL$ $ KL = 9({6}) + 9$ Simplify: $ {KL = 54 + 9}$ Simplify to find ${KL}$ : $ {KL = 63}$